What's more, workers discovered a fiber-optic line that runs the length of the Paramount Boulevard overpass, which was significantly damaged by a tanker truck explosion on the freeway below.

Cutting the line, Chandler said, would disrupt phone service for nearby businesses and homes.

The new developments mean that crews have to come up with an alternative plan to tear down the damaged span.

Caltrans officials had said they hoped the 60 Freeway, which had been closed between the 710 and 605 freeways, would be fully reopened by noon Friday. A portion of the freeway was reopened Thursday afternoon.

Officials had been waiting for test results of concrete on the part of the bridge over the westbound freeway lanes, which would determine whether they also need to demolish that side of the bridge.

If that section also had to be demolished, officials said, the freeway would not open until about 5 p.m.

The test results were returned Friday night, but agency officials in Sacramento were not releasing the findings, citing the need to conduct additional analysis, Chandler said.

"They want to have a second set of eyes before they take action," he told The Times.

The bottom line, he said, the opening of the 60 Freeway would probably be delayed. "It's most likely not going to be tomorrow at 12 or 5," he said.